On a moonless night amid choppy waves and gusty breezes, a 106-foot Brazilian yacht headed for the Bahamas sank to its final resting place in deep, unrecoverable waters more than a dozen miles off the coast of Lauderdale-by-the-Sea.

The first mayday call from the Serena III reporting a sinking vessel with 13 people on board went out about 6 p.m. Monday, officials said.

Six passengers — including registered owner Richard Paul Matheson of Brazil — six crew members and the captain were rescued without injury by the U.S. Coast Guard and taken to its Miami Beach base aboard a cutter. The yacht's port of call was listed as Rio de Janeiro.

"About 25 minutes after the last person was taken off the vessel is when the vessel completely sunk," said Coast Guard Petty Officer Jon-Paul Rios.

The 4-year-old custom-built yacht sank in about 1,200 feet of "deep, unrecoverable water," where it will remain, said Sea Tow Capt. Tim Morgan. He estimated the vessel's value at $10 million to $15 million.

Yacht sinks off off the coast of Lauderdale-by-the-Sea

Yacht sinks off off the coast of Lauderdale-by-the-Sea. Photo courtesy of Sea Tow

Yacht sinks off off the coast of Lauderdale-by-the-Sea. Photo courtesy of Sea Tow

"From start to finish it was about an hour and 49 minutes from the initial mayday call to the time it slipped below the waves," Morgan said.

Using an infrared camera, the U.S. Coast Guard captured dramatic video of the vessel listing before it slipped below the dark, choppy surface in a puff of smoke.

Morgan said he was the third boat on scene about 30 minutes after the initial call for help.

"The vessel was already listing about 15 degrees to the port side and every subsequent roll it would settle deeper and deeper into the water," Morgan said. "The stern of the vessel was under and we just observed it getting worse. The condition kept deteriorating and in such a rapid fashion."

Coast Guard rescue

Photos courtesy of the U.S. Coast Guard

13 people who were rescued by the Coast Guard from a sinking yacht several miles off Lauderdale-by-the-Sea were brought the agency's station in Miami Beach.

13 people who were rescued by the Coast Guard from a sinking yacht several miles off Lauderdale-by-the-Sea were brought the agency's station in Miami Beach.

(Photos courtesy of the U.S. Coast Guard)

The ship had left Port Everglades and was on its way to the Bahamas when it started taking on water.

The reason the vessel sank remains under investigation, but there was speculation that the bottom of the boat might have struck something as it left port.

"It was reported that they thought they soft grounded just outside of Port Everglades Inlet," said Marilyn Fajardo, a spokeswoman for the U.S. Coast Guard. "The captain reported this to the Coast Guard."

Matheson could not be reached for comment Tuesday.

A Coast Guard plane was the first responder to the scene. Its crew lowered a small gas pump to a nearby fishing boat that carried it to the sinking ship, Morgan said.

"For something that size, taking on that much water, it really wasn't going to do that much," Morgan said.

The fishermen had a tough time communicating with the Brazilians aboard the sinking yacht. "They were foreign speakers," Morgan said. "There was a language barrier."

"It was a moonless night, the moon hadn't risen yet so it was very dark," Morgan said. "The seas were three- to five-foot chop out there. It was very difficult for us to launch at full speed. The winds were blowing at about 15 knots out of the east/southeast, so it was a pretty rough ride."

Morgan said he instinctively knew even before he got there that the yacht would not be salvageable.

"It's not going to be recoverable, it's not financially feasible to raise a vessel from that deep of water. There's not enough value there," Morgan said. "We're just glad everybody got out safe and sound."

Sea Tow crews recovered an 18-foot tender, a jet ski, a life raft and some luggage, Morgan said.